Hi... Im trying Poser animation for last two months , after trial , error , and reading very helpfull threads by people here ( Rosity) , I could make very basic animation . But spline mode still make me confuse , can anyone tell me , when i should use green spline or orange ones ? Base on many threads here , many people recommended to use orange spline ,( maybe i know the answer because this interpolation keep poses influencing each other) So .. why poser give the green ones? Sorry , maybe this threads sound too ambitigious or stupidize , ( since orange spline interpolation answer many problem in poser animation) but i think i should know for improve my animation later thankz

Natural movement tends to be sinusoidal. Consider a figure swinging its leg forwards then back. It will start off slow, speed up in the middle of the swing to a constant velocity then slow down at the end. Poser enables this type of movement by using the Spline Section. If you used Linier then the movement will tend to look mechanical or robotic. The difficulty comes when you want to swing the leg back again. Poser interpolates the curve based on all the available key frames. In this instance you'll have one at the start, middle and end of the movement. If you alter the value of the backward swing key frame you will find that you are affecting the start of the swing which you may not want. The solution is to use a spline break on the forward swing key frame. This effectively isolates the movement into two sections. The swing back will not affect the swing forward.

To explain further look at this screenshot.

1. The starting point.
2. Keyframe to enable the outward swing of the leg to be adjusted
3. Full extent of the forward swing. Spline break key frame.
4. Keyframe to enable the backward swing to be adjusted.
5. The rear swing keyframe.
6. Final frame to bring the motion back to the start.

Note that because keyframe 3 is a spline break then moving keyframe 2 will not affect the back swing. Similarly moving keyframe 4 will not affect the front swing. Moving keyframe 4 will however affect what happens after keyframe 5, notice the over swing.

Where ever possible I use Spline Section, breaking the separate motions up with spline breaks. If you would like the PZ3 of this scene please email me at pcooke@philc.net and I'll be glad to send it by return.

Phil, you've been around since then, did you ever read my old Animation Primer? I dealt with exactly this question. I don't have it anymore, that was a number of years ago, but I'm working on a comprehensive cd full of animation tutorials right now. Anyway, you've got the right answer, Phil, (as a matter of fact I'm going to experiment some more with broken splines myself now...)but I want to clarify: A lot of people suggest this very thing, that using Linear(Orange Spline) interpolation is the best way or even the only way to animate. In reality, linear interpolation is really just there to replicate mechanical movement. For organic movement, you have to go with Spline (Green Spline) Interpolation. But the problem most beginners (And some experts) have, is keyframe positioning. If You have two keyframes far apart, (shown here on frame 1 and 15) and then you put a keyframe close to one of them (Frame 17) there's going to be a huge unwanted peak in the middle (right around nine and ten). While it's true that linear interpolation would not give you this peak, It also won't give you the "Ease-in/Ease-out" necessary for realistic organic animation. A better solution is shown here: Adding in keyframes in the middle (frames 9 and 12) lessens the peak and gives a rather natural motion. The overswing is still there on frame 14, but now the arc is more natural, and the forearm no longer bends INTO the upper arm, vanishing. Another possible solution to this problem would be to move the keyframe on frame sixteen, but sometimes you'll need very quick movement. Another thing to remember is that the curve of the spline will tell you how fast the object is moving. If the spline is shallow, almost horizontal, the object is moving slowly. If it's steep, nearly vertical, the object is moving very quickly. Now for my question: Phil, what do you feel are the advantages of breaking the spline, and could you give a breif example of when and why you would break it?

Actually, I took another look at your previous reply, Phil, and I get where and why to break. I'm going to have to incorporate that into my tutorials and my workflow....

thanks alot.. this is very usefull explaination thanks again